JP2023014849A - Toner for electrostatic charge image development and method for manufacturing toner for electrostatic charge image development - Google Patents

Abstract

To provide toner for electrostatic charge image development which is improved in low-temperature fixability and is excellent in anti-offset property, and a method for manufacturing toner for electrostatic charge image development.SOLUTION: The present invention includes toner for electrostatic charge image development that contains: binding resin; a colorant; a charge control agent; wax; and a dimethylpolysiloxane while they are mixed, wherein the toner for electrostatic charge image development contains, with respect to 100 pts.wt.of the binding resin, 1 pt.wt. or more and 13 pts.wt. or less of the wax, and 0.5 pt.wt.or more and 5 pts.wt. or less of the dimethylpolysiloxane, and further contains, as an external additive, at least one selected from a group consisting of amorphous silica and titanium oxide.SELECTED DRAWING: Figure 1

Description

The present invention relates to a toner for developing an electrostatic charge image and a method for producing the toner for developing an electrostatic charge image. Regarding the method.

An electrostatic charge image developing toner used in an electrophotographic system mainly contains a binder resin, a colorant and a charge control agent, and further contains additives such as a release agent and inorganic fine particles as necessary. These components are pre-mixed, heated and kneaded by heat melting, then pulverized and classified to produce the mother toner. An external additive is externally added to this mother toner to produce a toner.

For example, Patent Document 1 (Japanese Patent Laid-Open No. 2003-98757) discloses that the toner has good fluidity, heat resistance, durability, and storage stability, and the deterioration of the life of the developer due to carrier spent due to the toner and the photoreceptor filling due to the toner. In particular, the energy required for fixing is small, and the temperature and pressure of the hot roller can be lowered when the hot roller fixing method is used. Developers and electrophotographic devices with peel strength and rub strength have been proposed.

The developer and the electrophotographic apparatus described in Patent Document 1 include a toner for developing an electrostatic charge image containing at least a fixing resin, a colorant, and a wax, and a wax having a number average molecular weight of 1000 or less as a constituent of the toner. , the carrier has a bulk specific gravity of 2.0 g/cm ³ or less, and the magnetic material content is 30 to 99 wt % with respect to the total amount of the carrier.

Patent Document 2 (Japanese Patent Application Laid-Open No. 2000-10337) discloses that it can satisfy fixability, anti-offset property, and storage stability, can maintain high-performance developability even when waste toner is recycled, and has a photoreceptor and a developing member. In addition, in an electrophotographic apparatus equipped with a transfer system using a transfer roller, it is possible to suppress intermediate transfer defects and achieve highly efficient transfer. In addition, there has been proposed a toner capable of preventing the occurrence of filming on a photoreceptor with high density and low background fogging.

The toner described in Japanese Patent Laid-Open No. 2002-200001 is a toner which is composed of ester wax having a specific melting point, hydrophobic silica fine powder, and magnetic fine powder, and which is subjected to surface modification treatment with hot air.

Patent Document 3 (Japanese Patent Application Laid-Open No. 2017-151428) proposes a toner that satisfies low-temperature fixability and anti-blocking properties and can exhibit sufficient chargeability even in a high-temperature, high-humidity environment. .

The toner described in Patent Document 3 is obtained by melting and kneading a resin composition containing a binder resin, a colorant, a hydrocarbon wax, and a wax dispersant, cooling the kneaded product, and pulverizing the obtained cooled product. A toner having toner particles produced through a step of heat-treating the resin particles obtained by the above method, wherein the wax dispersant is a polymer obtained by graft polymerization of a styrene-acrylic polymer to polypropylene, and the styrene-acrylic polymer is is a polymer having a monomer unit derived from cycloalkyl (meth)acrylate, and is specified when the melting point (° C.) of polypropylene is Mp (p) and the melting point (° C.) of hydrocarbon wax is Mp (w) It satisfies the relationship between

Patent Document 4 (Japanese Patent Application Laid-Open No. 2017-54001) proposes a toner having good transferability even when a plasticizer such as a crystalline material is used and thermal spheroidization is performed.

The toner described in Patent Document 4 is produced by melt-kneading a mixture containing a binder resin, a hydrocarbon wax, a polymer having a structure obtained by reacting a vinyl resin component and a hydrocarbon compound, and hydrophobically treated inorganic fine particles. , in the toner having toner particles obtained by pulverizing the obtained kneaded material and heat-treating the obtained pulverized material, the binder resin contains a crystalline polyester resin and an amorphous polyester resin; The content of the crystalline polyester resin is 1.0 parts by mass or more and 15.0 parts by mass or less with respect to 100.0 parts by mass of the amorphous polyester resin, and the toner has a weight average particle diameter (D4) of It is 3.0 μm or more and 10.0 μm or less, and the toner has the inorganic fine particles in a region of 0.3 μm or more inside from the surface.

Patent Document 5 (Japanese Unexamined Patent Application Publication No. 2017-3901) proposes a toner that can satisfy both low-temperature fixability and charge stability even in a toner using a plasticizer such as a crystalline material. .

The toner described in Patent Document 5 is a toner containing toner particles obtained by a melt-kneading method of a toner composition containing a binder resin, inorganic fine particles A, and inorganic fine particles B, wherein the binder resin is a crystalline polyester resin. and an amorphous polyester resin, the content of the crystalline polyester resin is within a specific range, the D4 of the toner particles is 3.0 μm or more and 10.0 μm or less, and the toner particles are toner The particles have the inorganic fine particles A and B inside the particles, the toner particles contain a specific amount of the inorganic fine particles A and B with respect to 100 parts by mass of the amorphous polyester, and D1 of the inorganic fine particles A is The toner has a particle size of 80 nm or more and 300 nm or less, and D1 of the inorganic fine particles B is 0.05 times or more and 0.40 times or less of D1 of the inorganic fine particles A.

JP-A-2003-98757 JP-A-2000-10337 JP 2017-151428 A Japanese Patent Application Laid-Open No. 2017-54001 Japanese Patent Application Laid-Open No. 2017-3901

In the one-component development method, the developer is composed of only toner, and in the two-component development method, the developer is composed of toner and a ferrite carrier composed of magnetic particles.
The one-component development system is a system in which toner is charged by contact with a metal blade, a toner layer is formed on a developing roller, and the toner is transferred from a photoreceptor to paper.
The two-component development method is a system in which a ferrite carrier and toner are triboelectrically charged, the toner is transferred from a magnet roller to a photoreceptor, and the toner on the photoreceptor is transferred to paper.

In electrophotography using toner, in the fixing process, when the toner is heated by a fixing roll, the binder resin is softened and the wax added in the resin is melted by heat to become liquid.
When pressure is applied from the fixing roll, the liquefied wax exudes from the binder resin and migrates to the surface of the fixing roll, thereby preventing the toner from adhering to the fixing roll due to the release force of the wax. The liquefied wax also plays a role of softening the binder resin and assisting the fixation of the toner onto the print medium.
Conventionally, a binder resin with a high softening point and a wax with a high melting point are used as toner, and fixing is performed at high temperatures.
In recent years, however, there is a demand for low-temperature fixing from the viewpoint of energy saving. Therefore, it has been proposed to use a binder resin with a low softening point and a wax with a low melting point that can be fixed at a low temperature.

However, since the binder resin and the wax contained in the toner have poor compatibility, it is difficult to disperse the wax even if a large kneading shear is applied to the resin composition containing the binder resin and the wax. Therefore, there is a problem that a part of the wax is exposed on the surface of the toner and the toner is fused to the metal blade. Furthermore, there are problems of filming on the photoreceptor and carrier contamination.
In addition, in recent years, the low-temperature fixing, high-definition, and high-speed printing of toner have progressed, and in the formulation of toner, a large amount of wax is added, so the above problems are becoming more prominent. .

Further, in order to improve physical properties such as toner transfer efficiency and image density, it is also necessary to sphere the pulverized toner. However, since the toner is heated at a high temperature (from 200° C. to 400° C.) in the step of spheroidizing the pulverized toner, the wax is likely to be exposed on the surface of the toner, further exacerbating the above problem.

In order to solve such problems, the toners described in Patent Documents 1 and 2 use a specific wax, Patent Document 3 uses a specific binder resin and a wax dispersant, and Patent Document 4 and Patent Documents Document 5 uses a specific binder resin.
However, with the conventional methods, it has not been possible to realize an electrostatic charge image developing toner which can improve low-temperature fixability, has excellent offset resistance, and can suppress the occurrence of filming on a photoreceptor and carrier contamination. .

The present inventor has arrived at the present invention by discovering that the addition of dimethylpolysiloxane interacts with the wax to solve the above problems.
SUMMARY OF THE INVENTION It is an object of the present invention to provide a toner for developing an electrostatic charge image and a method for producing a toner for developing an electrostatic charge image, which can improve the low-temperature fixability and prevent the harmful effects of wax exudation from the toner.
Another object of the present invention is to provide a toner for developing an electrostatic charge image and a method for producing the toner for developing an electrostatic charge image which suppress coalescence of the toner.
Another object of the present invention is to provide a toner for developing an electrostatic charge image, and a method for producing the toner for developing an electrostatic charge image, which has improved low-temperature fixability and suppresses poor printing due to bleeding such as filming onto a photoreceptor and carrier contamination. is to provide
Another object of the present invention is to provide a toner for developing an electrostatic charge image, which has a low toner concentration and can prevent carrier contamination, and a method for producing the toner for developing an electrostatic charge image.
Another object of the present invention is to provide a toner for developing an electrostatic charge image with high image density and excellent image uniformity, and a method for producing the toner for developing an electrostatic charge image.

(1)
An electrostatic charge image developing toner according to one aspect contains a binder resin, a colorant, a charge control agent, wax, and dimethylpolysiloxane as an internal additive.

The electrostatic charge image developing toner of the present invention contains a binder resin, a colorant, and a charge control agent, and contains dimethylpolysiloxane as an internal additive. It is possible to obtain a toner in which harmful effects caused by wax are suppressed.
That is, in order to achieve low-temperature fixing, it is necessary to include a large amount of wax having a low melting point in the toner. Bad wax tends to appear on the surface of the toner, and printing defects have occurred due to the exudation of the wax. In particular, in the case of spherical toner, since wax tends to appear in the vicinity of the surface of the toner during the heat treatment process, poor printing is likely to occur due to exudation of the wax.
On the other hand, dimethylpolysiloxane used in the present invention is superior to wax in lubricity, releasability and dispersibility. Further, since dimethylpolysiloxane and wax are mixed and contained as an internal additive, the compatibility between the wax and the binder resin is improved, and the exudation of the wax is preferably prevented even when heated. It is possible to obtain a toner for electrostatic charge image development that achieves both a high fixing rate and a wide offset region. In addition, the releasability from the heat roller (heat roller) during fixing can be improved, and the anti-offset property can be enhanced. It is considered that when the dimethylpolysiloxane of the present invention is internally added, exposure is suppressed regardless of the acid value of the wax.

Furthermore, since the addition of dimethylpolysiloxane can improve the dispersibility of the wax, it is possible to prevent the wax and/or the dimethylpolysiloxane from liberating from the toner and adhering (filming) to the photoreceptor during development. can be done. In particular, even when the toner is spheroidized, the wax is prevented from exuding, so that the generation of coalesced particles can be suppressed, and an increase in the particle size of the toner can be preferably prevented.
In the case of a two-component printer, carrier spent due to exposure of wax can be prevented, and even pulverized toner containing a large amount of wax has a low toner concentration and can prevent carrier contamination. Therefore, it is possible to stably form high-quality images over a long period of time.

In particular, in a spherical toner that has undergone a spheroidizing treatment, the wax tends to be exposed to the surface during the heat treatment, so that the problem caused by the exudation of the wax has been a serious problem. However, according to the toner for developing an electrostatic charge image of the present invention, it is possible to preferably suppress the adverse effects caused by exudation of the wax.
Further, even in pulverized toner which is not subjected to spheroidizing treatment, according to the toner for electrostatic charge image development of the present invention, the binding resin and wax can be preferably compatible with each other. can be suppressed. Similarly, the present invention can be applied to positively charged toner as well as negatively charged toner, and can be applied to magnetic toner as well as non-magnetic toner. According to the present invention, even a toner containing a large amount of wax can be made into a toner having high image density and excellent image uniformity.

(2)
A toner for developing an electrostatic charge image according to a second aspect of the present invention is a toner for developing an electrostatic charge image according to one aspect, wherein 1 part by weight or more and 13 parts by weight or less of a wax is contained with respect to 100 parts by weight of a binder resin, and dimethylpolysiloxane may be contained in an amount of 0.5 parts by weight or more and less than 5 parts by weight.

When the blending ratio of the binder resin, wax and dimethylpolysiloxane is in the above ratio, the wax is dispersed relatively uniformly in the toner, and the wax is prevented from exuding to the toner surface.
In particular, when the content of dimethylpolysiloxane is within the above range, the toner for electrostatic charge image development having excellent anti-offset properties can be obtained.

(3)
A toner for developing an electrostatic charge image according to a third invention is the toner for developing an electrostatic charge image according to one aspect or the second invention, wherein the wax is 1 part by weight, and the dimethylpolysiloxane is 0.1 part by weight or more. 1.0 parts by weight or less may be contained.

When the blending ratio of the wax and the dimethylpolysiloxane in the toner is such a ratio, the wax is easily dispersed in the toner, and the wax is prevented from exuding onto the surface of the toner.

(4)
A toner for developing an electrostatic charge image according to a fourth aspect of the invention is the toner for developing an electrostatic charge image according to any one of the first aspect to the third aspect of the invention, further comprising, as an external additive, from the group consisting of amorphous silica and titanium oxide. It may contain at least one selected.

This improves the dispersibility, fluidity and chargeability of the toner. In particular, it is preferable to use amorphous silica particles as an external additive, and by including 0.1 parts by weight or more and 5 parts by weight or less per 100 parts by weight of the toner, the dispersibility, fluidity, and chargeability of the toner can be preferably improved. can be done.
Conventionally, when an external additive with a small particle size is used, the hydrophobizing component of the external additive has affinity with the wax component in the toner, and the external additive coverage on the toner surface increases as the amount added increases. Therefore, there is a problem that the wax component seeps out onto the surface of the fixed image.
However, the toner for electrostatic charge image development of the present invention is excellent in dispersibility, fluidity, chargeability and fixability because the exudation of the wax component to the toner surface is prevented, thereby suppressing such problems. toner.

(5)
A toner for developing an electrostatic charge image according to a fifth invention is the toner for developing an electrostatic charge image according to any one of the first aspect to the fourth invention, wherein the wax is selected from the group consisting of an ester wax and a Fischer-Tropsch wax. may be at least one of

As a result, the compatibility between the wax and the binder resin is further improved, so the wax is prevented from exuding, and the toner for electrostatic image development achieves both a higher fixing rate, a wide offset area, and prevention of filming. can be

(6)
A toner for developing an electrostatic charge image according to a sixth invention is the toner for developing an electrostatic charge image according to any one of the first aspect to the fifth invention, wherein the wax has a melting point of 65° C. or higher and 95° C. or lower. The acid value may be 0.1 mgKOH/g or more and 25 mgKOH/g or less.

When the acid value is 0.1 mgKOH/g or more, aggregation of the wax can be prevented, and when the acid value is 25 mgKOH/g or less, it is more preferable from the viewpoint of work efficiency, hygroscopicity, and improvement of printed images. It is presumed that the high acid value of the wax causes the acidic groups such as carboxylic acid present on the toner surface to form hydrogen bonds with the acidic groups of the polyester resin, thereby suppressing the exposure of the wax. .
The acid value measurement method conforms to JIS K0070-1992.

(7)
The toner for developing an electrostatic charge image according to the seventh invention may be the toner for developing an electrostatic charge image according to any one of the first aspect to the sixth invention, wherein the binder resin may be a polyester-based resin.

As a result, the compatibility between the wax and the binder resin is further improved, so that the wax is prevented from exuding, and a toner for electrostatic charge image development that achieves both a higher fixing rate and a wide offset region can be obtained. .

A method for producing a toner for developing an electrostatic charge image according to another aspect includes kneading a binder resin, a coloring agent, a charge control agent, wax, and dimethylpolysiloxane to obtain a kneaded product. a step of pulverizing the kneaded material to obtain a mother toner having an average particle size of 5 μm or more and 10 μm or less, a pretreatment step of adding amorphous silica or titanium oxide to the mother toner, and a heat treatment step of heat-treating the mother toner; includes.

As a result, the compatibility between the wax and the binder resin is improved, and the exudation of the wax is prevented, so that a toner for electrostatic charge image development that achieves both a high fixing rate and a wide offset range can be obtained. .

1 is an example of a SEM photograph of heat-treated spherical toner; An example of wax fused to a metal blade. It is an example of wax filmed on a photoreceptor. 1 is an example of a SEM photograph of the toner of Example 1. FIG. 1 is an example of a SEM photograph of the toner of Comparative Example 1. FIG.

[Embodiment]
The electrostatic charge image developing toner of the present embodiment contains a binder resin, a colorant, a charge control agent, wax, and dimethylpolysiloxane.
In the present embodiment, a toner whose surface is made spherical by heat treatment described later is referred to as spherical toner, and a toner that has not been subjected to heat treatment (spheroidization treatment) after pulverization is referred to as pulverized toner. The toner is sometimes called magnetic toner.

(Binder resin)
As the binder resin used in the present invention, all conventionally known resins can be used.
For example, styrene, poly-α-stillstyrene, styrene-chlorostyrene copolymer, styrene-propylene copolymer, styrene-butadiene copolymer, styrene-vinyl chloride copolymer, styrene-vinyl acetate copolymer, styrene -Styrenes such as maleic acid copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-methyl chloroacrylate copolymer, styrene-acrylonitrile-acrylic acid ester copolymer, etc. resins (styrene or homopolymers or copolymers containing styrene substitution), epoxy resins, vinyl chloride resins, rosin-modified maleic acid resins, phenolic resins, polyethylene resins, polypropylene resins, petroleum resins, polyurethane resins, ketone resins, Examples include ethylene-ethyl acrylate copolymer, xylene resin, polyvinyl butyrate resin, styrene acrylic resin, etc. These resins may be used in combination with polyester resins and epoxy resins, or may be used alone. Moreover, you may use together 2 or more types.

Among these resins, it is preferable to contain a polyester resin or a styrene acrylic resin as the binder resin. A polyester resin is generally suitable for use as a binder resin in the present invention because it can be fixed at a low temperature while maintaining heat-resistant storage stability compared to other resins.

Polyester resins are obtained by condensation polymerization of alcohols and carboxylic acids.
Examples of alcohols used include glycols such as ethylene glycol, diene glycol, triethylene glycol and propylene glycol; etherified bisphenols such as 1,4-bis(hydroxymeta)cyclohexane and bisphenol A; and trihydric or higher polyhydric alcohol monomers.

Examples of carboxylic acids include divalent organic acid monomers such as maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid and malonic acid, 1,2,4-benzenetricarboxylic acid, 1, 2,5-benzenetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methylenecarboxypropane , 1,2,7,8-octanetetracarboxylic acid, and trivalent or higher polyvalent carboxylic acid monomers.
The glass transition point (Tg) of the polyester resin is preferably 30° C. or higher and 70° C. or lower, more preferably 40° C. or higher and 60° C. or lower.

(coloring agent)
As the colorant used in the present invention, all pigments and dyes conventionally known as colorants for toners can be used.
Specific examples include carbon black, lamp black, iron black, ultramarine blue, nigrosine dye, aniline blue, chalco oil blue, oil black, and azo oil black, but are not particularly limited.

The amount of the coloring agent used is preferably 1 part by weight or more and 10 parts by weight or less, more preferably 3 parts by weight or more and 7 parts by weight or less per 100 parts by weight of the binder resin.

When the toner of the present invention is used as a magnetic toner, iron oxides such as magnetite, maghemite, and ferrite; metals such as iron, cobalt, and nickel; or these metals together with aluminum, copper, magnesium, tin, and zinc. , alloys of metals such as beryllium, calcium, manganese, selenium, titanium, tungsten, vanadium, and mixtures thereof. Also, other colorants can be added.

(Charge control agent)
In order to control the polarity, the toner for electrostatic image development of the present invention may contain a charge control agent. In particular, it is preferable to control the chargeability of the toner used in the one-component development system with a charge control agent.
Examples of charge control agents include nigrosine dyes, quaternary ammonium salts, amino group-containing polymers, metal-containing azo dyes, salicylic acid complex compounds, phenol compounds, and the like.
The charge control agent is preferably used in an amount of 0.5 to 10 parts by weight, more preferably 1 to 5 parts by weight, per 100 parts by weight of the toner in the case of a one-component development system.

(wax)
In the toner of the present invention, wax is contained in the toner from the viewpoint of improving releasability from the fixing member during fixing and improving low-temperature fixability.
Waxes used in the present invention include, for example, low molecular weight polyolefins such as polyethylene; ester waxes such as stearyl stearate; plant waxes such as carnauba wax, rice wax, candelilla wax, wood wax and jojoba oil; animal waxes such as beeswax; mineral and petroleum waxes such as montan wax, ozokerite, ceresin, paraffin wax, microcrystalline wax, Fischer-Tropsch wax and ester wax; and modified products thereof. These waxes can be used alone or in combination.
In particular, aliphatic hydrocarbons such as ester waxes and Fischer-Tropsch waxes are preferably used. The Fischer-Tropsch wax may be a modified Fischer-Tropsch wax. The wax preferably has a melting point of 110° C. or lower, more preferably 60° C. or higher and 100° C. or lower, and particularly preferably 65° C. or higher and 95° C. or lower.

The acid value of the wax according to the present invention is preferably 0.05 mgKOH/g or more and 30 mgKOH/g or less, more preferably 0.1 mgKOH/g or more and 25 mgKOH/g or less. Thereby, a good printed image can be obtained. The acid value measurement method conforms to JIS K0070-1992.

The content of the wax is preferably 1 part by weight or more and 13 parts by weight or less, more preferably 1.2 parts by weight or more and 10 parts by weight or less, and still more preferably, with respect to 100 parts by weight of the binder resin. is 1.5 parts by weight or more and 8 parts by weight or less.

(dimethylpolysiloxane)
In the present invention, by internally adding dimethylpolysiloxane to the binder resin and the wax and mixing them, the exudation of the wax can be preferably prevented. Therefore, coalescence of toner particles is suppressed, and an increase in particle size of toner can be preferably prevented.
The content of dimethylpolysiloxane is preferably 0.5 parts by weight or more and less than 5 parts by weight, more preferably 1 part by weight or more and 4 parts by weight or less, and even more preferably, with respect to 100 parts by weight of the binder resin. is 1.5 parts by weight or more and 3.0 parts by weight or less. As a result, the printed image can be of high quality.

（式１）
本実施形態で使用されるジメチルポリシロキサンは、ＯＨ基またはアミノ基等に変性されたジメチルポリシロキサンであってもよく、アルカリ性であってもよい。これによって、エステルワックスまたはフィッシャートロプシュワックスなどの脂肪族炭化水素系ワックスと好ましく相溶させることができ、フィルミング等の発生を好ましく防止できると考えられる。 A general chemical structural formula of dimethylpolysiloxane is shown in Formula 1 below.

(Formula 1)
The dimethylpolysiloxane used in the present embodiment may be dimethylpolysiloxane modified with an OH group, an amino group, or the like, and may be alkaline. It is believed that this makes it possible to favorably dissolve with an aliphatic hydrocarbon wax such as an ester wax or a Fischer-Tropsch wax, thereby favorably preventing the occurrence of filming or the like.

As described above, the dispersibility of wax can be improved by adding dimethylpolysiloxane to the toner. That is, the mixture of wax and dimethylpolysiloxane can enhance compatibility with the binder resin compared to the case of using only wax. As a result, it is possible to improve the dispersibility of the wax.
On the other hand, if the content of dimethylpolysiloxane exceeds the upper limit, it may affect the fixability of the spherical toner.

Also, the dispersibility of the wax can be adjusted by changing the mixing ratio of the wax and the dimethylpolysiloxane.
The wax may be contained in an amount of 1 part by weight or more and 13 parts by weight or less per 100 parts by weight of the binder resin. In addition, dimethylpolysiloxane can be contained in the range of 0.5 parts by weight or more and less than 5.0 parts by weight with respect to 100 parts by weight of the binder resin, and the content should be 1 part by weight or more and 4 parts by weight or less. is preferred.
If the wax content is less than 1 weight, the low-temperature fixability tends to be poor.
On the other hand, when the content of dimethylpolysiloxane is less than the above range, the dispersibility of the wax tends to be lowered. sometimes.

The ratio of the content of wax to the content of dimethylpolysiloxane is preferably 0.1 part by weight or more and 1.0 part by weight or less of dimethylpolysiloxane per 1 part by weight of wax. More preferably, the amount of dimethylpolysiloxane is 0.2 parts by weight or more and 0.8 parts by weight or less per 1 part by weight of wax.
If the wax content in the toner is less than the above range, the low-temperature fixability tends to be poor. Easier to expose.
Similarly, if the content of dimethylpolysiloxane in the toner is less than the above range, the dispersibility of the wax tends to decrease, and if it exceeds the above range, the thixotropy increases and fixability is affected. There is

(Additive)
The toner of the present invention can contain at least one selected from the group consisting of amorphous silica and titanium oxide as an additive in the pretreatment step.
In order to impart high fluidity to the toner, the additive can be selected from those having an average primary particle size of 0.001 μm or more and 1 μm or less, preferably 0.005 μm or more and 0.1 μm or less. Specifically, it is preferable to use amorphous silica particles having a BET specific surface area of 30 m ² /g or more and 300 m ² /g or less with respect to the toner surface area.
The additive is preferably added in an amount of 0.1 to 5 parts by weight, more preferably 0.1 to 3 parts by weight, and even more preferably 100 parts by weight of the toner. is in the range of 0.2 parts by weight or more and 2 parts by weight or less. If this upper limit is exceeded, the fixing offset property may be affected due to insufficient melting.
Furthermore, inorganic fine powders other than amorphous silica and titanium oxide fine powders can be used together. Usable inorganic fine powders include aluminum oxides and aliphatic metal salts.

(external additive)
In the present invention, at least one selected from the group consisting of amorphous silica, titanium oxide, aluminum oxide, strontium titanate, organic fine particles, and silicone oil can be contained as an external additive that imparts fluidity. Among these, it is preferable to use silica or titanium oxide. The external addition step of adding these external additives can be performed for any of spherical toner, pulverized toner and magnetic toner.
Silica or titanium oxide used as an external additive may have a particle size of 0.001 μm or more and 1.0 μm or less. This silica or titanium oxide can be used after its surface has been previously hydrophobized with a silane coupling agent, silicone oil, or the like.

Silica or titanium oxide used in the present invention is preferably contained in the range of 0.1 parts by weight or more and 4.0 parts by weight or less with respect to 100 parts by weight of the toner particles.
By adding silica as an external additive, it is possible to improve chargeability, improve image uniformity, etc., and improve fluidity. When the amount of silica added is large, the charge increases and fogging and scattering are eliminated, but the density of the image may become low.
Further, by adding titanium oxide as an external additive, excessive charging is prevented and uniformity is improved. On the other hand, if the amount of titanium oxide added is too large, the charging may be low and the image density may be high.
In some cases, silica and titanium oxide as external additives can mitigate these problems by adjusting the particle size and surface treatment. For example, silica having a large particle size can be used as an anti-burial agent for other external additives.

[Toner manufacturing method]
The method for producing the toner of the present invention may be a conventionally known method, in which a binder resin, wax, colorant, charge control agent and others are mixed using a mixer or the like, and heated rolls (hot rolls), extruders or the like are used. After kneading with a kneader, the mixture is cooled and solidified, pulverized with a pulverizer such as a jet mill, and then classified.

The toner of this embodiment can be manufactured as follows.
(Kneading process)
First, a binder resin, a low softening point wax, dimethylpolysiloxane, a pigment or dye as a coloring agent, a charge control agent, and other additives are thoroughly mixed in a mixer such as a Henschel mixer or ball mill, The resulting mixture is melt-kneaded using a hot kneader such as a superheated roll kneader or an extruder to make the resin components compatible with each other. After dispersing or dissolving the solid, the obtained kneaded product is solidified by cooling, and then pulverized and classified to obtain a pulverized toner.

(Pretreatment step)
When performing a spheronization treatment (heat treatment), it is preferable to add an additive such as silica or titanium oxide for fluidization treatment. In this embodiment, amorphous silica is added to the mother toner.
In conventional toners, it was necessary to add a large amount of additives in order to prevent the wax from coalescing due to exposure. When the binder resin, wax, and dimethylpolysiloxane of the present invention are used, the generation of coalesced particles is suppressed, so the amount of fluidizing agent such as amorphous silica to be added can be preferably reduced.
The amount of the additive added in the pretreatment step of the present embodiment is preferably 0.2 parts by weight or more and 3 parts by weight or less, more preferably 0.5 parts by weight or more and 2 parts by weight, with respect to 100 parts by weight of the mother toner obtained in the pulverization process. It is more preferably 0.8 parts by weight or more and 1.5 parts by weight or less. As a result, the occurrence of filming or the like can be preferably prevented while preventing coalescence of particles.

(Heat treatment process)
Next, the pulverized toner that has undergone the pulverization step is subjected to gas phase treatment with hot air having a temperature higher than the glass transition point of the binder resin and the melting point of the wax. By doing so, the shape of the mother toner particles obtained by the kneading-pulverization method can be controlled to have a more uniform spherical shape, the smoothness of the toner surface can be improved, and the adhesion stress can be reduced.

In the present invention, in the toner manufacturing process, a step of treating the mother toner particles in the gas phase with hot air having a temperature higher than the glass transition point of the binder resin and the melting point of the wax is added to the pulverization step. As shown in , the particles are arranged in a more uniform shape, the smoothness of the toner particle surface is enhanced, and the adhesion stress is reduced. As a result, it is possible to improve the charging uniformity of the toner to be produced, and to produce a toner excellent in image performance.
In particular, in the present invention, dimethylpolysiloxane and wax are mixed and contained as an internal additive, so exudation of wax is preferably prevented. Therefore, since the wax is less likely to be exposed on the toner surface even if heat treatment is performed, coalescence of the toner powder can be preferably prevented.

(External addition process)
External additives such as silica or titanium oxide can be added as a fluidization treatment.
On the other hand, when the binder resin, wax and dimethylpolysiloxane of the present invention are used, the generation of coalesced particles is suppressed, so the amount of fluidizing agent such as silica to be added can be preferably reduced. As a result, it is possible to preferably prevent the occurrence of filming due to the external additive.
The amount of the external additive added in the external addition step of the present embodiment is preferably 0.2 parts by weight or more and 3 parts by weight or less, and 0.5 parts by weight or more with respect to 100 parts by weight of the mother toner obtained in the pulverization step. 2 parts by weight or less is more preferable, and 0.8 to 1.5 parts by weight is more preferable. As a result, it is possible to preferably prevent the occurrence of filming or the like while preventing coalescence of particles. It should be noted that a plurality of types of external additives can be combined.

<One-component developer>
The toner obtained as described above can be used in a one-component developer.
A one-component developer does not use a carrier containing a magnetic material, and is therefore suitable for full-color printing and the like. In addition, since control of carrier and toner densities is unnecessary, it is suitable for small devices.

When the toner of the present invention is used as a normal one-component toner, a method of forcibly triboelectrifying a developing sleeve using a blade or a roller and conveying the toner by adhering the toner onto the sleeve can be used. can.

<Two-component developer>
The two-component development method uses a developer mixed with a carrier containing magnetic powder in order to charge the toner. As the magnetic powder, iron oxide, magnetite, ferrite, etc. can be used.
In the two-component development method, the friction between the carrier and the toner gives the toner a high charge amount, so that the toner can be electrostatically adhered to the photoreceptor. Therefore, two-component developers are capable of high-speed printing.

When the toner of the present invention is used in a two-component developer, the carrier to be mixed and used may be powder having a particle size of about 30 μm or more and 50 μm or less, the main component of which is glass, iron, ferrite, nickel, zircon, silica, or the like. Alternatively, the powder may be used as a core material and coated with styrene-acrylic resin, silicone resin, polyamide resin, polyvinylidene fluoride resin, or the like. In recent years, a ferrite carrier is used as a carrier, and Cu--Zn, Mn--Mg--Sr, etc. are used as the core of the ferrite carrier. In this case, the particle size of the carrier is preferably 30 μm or more and 40 μm or less.
In the case of two-component toner, pulverized toner that is not subjected to heat treatment may be used. Furthermore, in recent years, a magnetic powder-containing resin carrier, in which magnetic powder is internally added, is sometimes used as a carrier.
In this specification, when necessary for distinction, a toner that has been subjected to heat treatment to give a spherical surface is referred to as spherical toner, and a toner that has not been subjected to heat treatment (spheroidization treatment) after pulverization is referred to as pulverized toner. A pulverized toner containing a magnetic substance is called a magnetic toner. When simply referred to as toner, there is no particular distinction.

When the toner of the present invention is used as a two-component developer, the toner and carrier are mixed at a toner concentration of 0.1% by weight or more and 50% by weight or less, more preferably 0.5% by weight. 20 wt % or less, more preferably 2 wt % or more and 13 wt % or less, still more preferably 3 wt % or more and 10 wt % or less. If the toner concentration is too low, the image density will be low.

Examples of carrier core materials include surface-oxidized or unoxidized iron, cobalt, nickel, copper, zinc, manganese, chromium, rare earth metals, alloys, compounds, oxides, and magnetic ferrites thereof. . Among them, those containing 98% by weight or more of ferrite carrier are preferably used.

An external additive such as silica or titanium oxide was added in an external addition step to the mother toner obtained in the pulverization step to obtain a pulverized toner. That is, by not performing the pretreatment process and the heat treatment process, a pulverized toner not subjected to the spheroidizing treatment was obtained.
The pulverized toner thus obtained was mixed with magnetic powder as a carrier to obtain a toner for two-component development.
Specifically, in the two-component development of this embodiment, as trickle development, a system is adopted in which toner and carrier are mixed and put into a toner cartridge, and the toner and carrier enter the developing machine. As a result, the carrier is always refreshed, and carrier spent and the like can be prevented. The ratio of toner and carrier in the toner cartridge was adjusted so that the ratio of toner:carrier was 80-90:20-10 (%).
In both trickle development and normal two-component development, the mixing ratio of toner and carrier inside the developing device is controlled by a magnetic permeability sensor or the like, and toner:carrier = 10 to 20:80 to 90 (%). ) is preferably controlled.

(Example 1)
[Kneading process]
100 parts by weight of a binder resin made of a polyester resin, 4 parts by weight of a pigment as a coloring agent, 2 parts by weight of a charge control agent (E-84 manufactured by Orient Chemical Industry Co., Ltd.), 5 parts by weight of an ester wax (RBW 101 PVITA manufactured by Clariant Japan), and Two parts by weight of dimethylpolysiloxane were mixed and kneaded with a twin-screw extruder (PCM manufactured by Ikegai Co., Ltd.).
The ester wax (RBW 101PVITA manufactured by Clariant Japan) used in Example 1 has a melting point of 78°C and an acid value of 20 mgKOH/g. 70%.
[Pulverization process]
Thereafter, the obtained kneaded material was pulverized by a jet pulverizer (I-5 manufactured by Nippon Pneumatic Co., Ltd.) so as to have an average particle size of 7 μm, thereby obtaining a mother toner.
[Pretreatment process]
To the obtained mother toner, 1 part by weight of amorphous silica (RY300 manufactured by Nippon Aerosil Co., Ltd.) was added as an additive for pretreatment of the heat treatment step.
[Heat treatment process]
Subsequently, the hot air temperature of the heat treatment device (MR-3 manufactured by Nippon Pneumatic Co., Ltd.) was adjusted to 300° C., and the mother toner was agitated with a hot air flow rate of 1.1 m ³ /L and a supply rate of 10 kg/h. .
[External addition process]
To 100 parts by weight of the heat-treated mother toner, 1 part by weight of amorphous silica and 0.2 parts by weight of titanium oxide were added as external additives to obtain the desired spherical toner. .

(Example 2)
In the kneading process, the same process as in Example 1 was performed except that 5 parts by weight of ester wax (WEP-9 manufactured by NOF Corporation) was used instead of ester wax (manufactured by Clariant Japan) to obtain a spherical toner. got
The ester wax (WEP-9 manufactured by NOF Corporation) used in Example 2 has a melting point of 67° C. and an acid value of 0.1 mgKOH/g.

(Example 3)
A spherical toner was obtained in the same manner as in Example 1, except that 5 parts by weight of modified Fischer-Tropsch wax was used instead of ester wax in the kneading step.
The modified Fischer-Tropsch wax used in Example 3 has a melting point of 90°C and an acid value of 3 mgKOH/g.

(Example 4)
A spherical toner was obtained in the same manner as in Example 1, except that 5 parts by weight of dimethylpolysiloxane was added in the kneading step.

(Example 5)
A spherical toner was obtained in the same manner as in Example 1, except that in the kneading step in Example 1, the wax was changed to a hydrocarbon wax (paraffin wax).
The hydrocarbon wax used in Example 5 has a melting point of 99°C.

(Example 6)
In the kneading step of Example 1, 5 parts by weight of modified Fischer-Tropsch wax was used instead of the ester wax, and the external addition step was performed without performing the pretreatment step and the heat treatment step.
In the external addition step, 1 part by weight of large particle size amorphous silica (80 m ² /g), 0.5 parts by weight of small particle size amorphous silica (260 m ² /g), titanium oxide (50 m ² /g) was added in an amount of 0.3 parts by weight to carry out an external addition treatment. Otherwise, the toner was obtained in the same manner as in Example 1.
As a result, a pulverized toner that was not subjected to the spheronization treatment was obtained.

(Example 7)
In the kneading step of Example 6, 5 parts by weight of amorphous silica (RY300 manufactured by Nippon Aerosil Co., Ltd.) was further added. A pulverized toner was obtained in the same manner as in Example 6 except for the above.

(Example 8)
In the kneading step of Example 6, 5 parts by weight of colloidal silica was further added. A pulverized toner was obtained in the same manner as in Example 6 except for the above.

(Example 9)
In the kneading step of Example 1, the polyester resin was replaced with a styrene acrylic resin, the pigment 4 parts by weight was replaced with magnetite 70 parts by weight (BL-11 manufactured by Titan Kogyo Co., Ltd.), and the charge control agent was 2 parts by weight. (E-84 manufactured by Orient Chemical Co., Ltd.) and ester wax (melting point 74° C., acid value 1 mgKOH/g or less) were adjusted to 10 parts by weight.
In the pulverization step, the toner was pulverized to an average particle size of 7 μm with a turbo pulverizer (T400-4RS110JP manufactured by Turbo Kogyo Co., Ltd.) to obtain a mother toner.
Then, the external addition process was performed in the same manner as in Example 1 without performing the pretreatment process and the heat treatment process.
As a result, a magnetic toner was obtained that was not subjected to the spheroidizing treatment.

(Comparative example 1)
A spherical toner was obtained in the same manner as in Example 1 except that dimethylpolysiloxane was not included in the kneading step in Example 1.

(Comparative example 2)
A spherical toner was obtained in the same manner as in Example 1 except that in the kneading step in Example 1, 2 parts by weight of amorphous silica (RY300 manufactured by Nippon Aerosil Co., Ltd.) was added instead of dimethylpolysiloxane.

(Comparative Example 3)
A spherical toner was obtained in the same manner as in Example 1, except that 2 parts by weight of colloidal silica was added instead of dimethylpolysiloxane in the kneading step in Example 1.

(Comparative Example 4)
In the kneading step in Example 1, no dimethylpolysiloxane was added, and in the pretreatment step, 1 part by weight of amorphous silica (RY300 manufactured by Nippon Aerosil Co., Ltd.) and 2 parts by weight of dimethylpolysiloxane were added. A spherical toner was obtained in the same manner as in Example 1 except for the above.

(Comparative Example 5)
A pulverized toner was obtained in the same manner as in Example 6, except that dimethylpolysiloxane was not added in the kneading step in Example 6.

(Comparative Example 6)
A magnetic toner was obtained in the same manner as in Example 9, except that dimethylpolysiloxane was not added in the kneading step in Example 9.

<Measurement of physical properties of toner>
The physical properties of each toner obtained were measured as follows.
(1) Measurement of Average Particle Size The average particle size of the toner was measured by the Coulter method. Spectris CDX-1000 was used as a measuring device, and a 1% NaCl aqueous solution was prepared using primary sodium chloride as an electrolytic solution. Cellpack PK-30L manufactured by Spectris can be used as the electrolyte. As a particle size measurement method, 0.1 mL or more and 5 mL or less of a surfactant, preferably alkylbenzene sulfonate, is added as a dispersant to 100 mL or more and 150 mL or less of this electrolytic aqueous solution, and 2 mg or more and 20 mg or less of a measurement sample is added. added.

The electrolytic solution in which the sample was suspended was subjected to dispersion treatment for about 1 minute in an ultrasonic disperser, and the volume and number of toner particles having a size of 2.007 μm or more were measured by the above-described measuring device using a 100 μm aperture as an aperture in 256 channel mode. was measured and the weight distribution was calculated.

(2) Circularity Measurement The circularity of the toner was measured using FPIA (registered trademark)-3000 (manufactured by Spectris Co., Ltd.). Specifically, the sample was blended with a solution of a surfactant in a commercially available special sheath liquid, and after ultrasonic dispersion was performed for 1 minute and dispersed, in the measurement condition HPF (high magnification imaging) mode, Measurement was performed at an appropriate concentration of 3000 HPFs detected. Within this range, the same reproducible measured value can be obtained. Circularity defined by the following formula was measured.
Circularity = (perimeter of a circle having the same projected area as the particle image)/(perimeter of the projected particle image)
The average circularity is a value calculated by adding the circularity of each particle and dividing by the total number of particles.

(3) Measurement of softening point The softening point was measured using a flow tester CFP-500D manufactured by Shimadzu Corporation. 1.3 g of the toners of the above examples and comparative examples were put into the layer preheated to 70° C., and a load of 15 kgf was applied to the diameter/length=0.5/1.0 mm, and the temperature was lowered by 4 mm from the extrusion starting point. softening point.

(4) Measurement of Amount of Remaining Wax A pure wax was heated at a rate of 6° C./min using a DSC3100 manufactured by MacScience to measure the amount of heat (J/g). Thereafter, the DSC measurement of the toner was performed in the same manner to measure the amount of heat of the wax contained in the toner, and the amount of residual wax in the toner was calculated.
That is, it was calculated by dividing the amount of heat absorbed by the toner (J/g) by the amount of heat absorbed by the pure wax (J/g) at the melting point temperature of the wax.
Amount of residual wax=(Amount of heat absorbed by wax in toner/Amount of heat absorbed by pure wax)×100

Various physical properties of the spherical toners obtained in Examples 1 to 5 and Comparative Examples 1 to 4 are shown below.

Next, various physical properties of the pulverized toner obtained in Examples 6 to 8 and Comparative Example 5 are shown below.

Next, various physical properties of the magnetic toners obtained in Example 9 and Comparative Example 6 are shown below.

It was confirmed that the spherical toner, the pulverized toner, and the magnetic toner, even if dimethylpolysiloxane was internally added to the binder resin and wax and kneaded, had no adverse effect on various physical properties.
In addition, it was confirmed that the particle size difference δ (μm) before and after the heat treatment did not substantially change in the example of the spherical toner. In other words, it is considered that the toner of the present invention did not undergo a change in particle size because the exudation of the wax was favorably prevented and coalescence of the toner powder was favorably prevented even after the heat treatment.

<SEM photography>
4 is an example of a SEM (Scanning Electron Microscope) photograph of the toner of Example 1, and FIG. 5 is an example of an SEM photograph of the toner of Comparative Example 1. FIG.

As shown in FIG. 4, the toner of Example 1 was confirmed to have no wax interface unevenness on the toner surface by heat treatment using dimethylpolysiloxane, and as shown in FIG. In this case, it was found that the interface unevenness of the wax appeared on the toner surface.

<Image quality evaluation>
As an evaluation of the toner for developing an electrostatic charge image and the method for producing the toner for developing an electrostatic charge image according to the present invention, the quality of a printed image using the obtained toner was evaluated.
The method for evaluating the printed image is as follows.

(1) Blade fusion:
8,000 A4 sheets were continuously printed in the vertical direction at a printing rate of 5%, and solid printing (solid printing) and the doctor blade were visually observed to confirm the presence or absence of fusion.
As shown in FIG. 2, when fusion was confirmed on the doctor blade, it was evaluated as x. When fusion was observed but the degree was light, it was evaluated as Δ.
(2) Filming:
8,000 A4 sheets were continuously printed in the longitudinal direction at a printing rate of 5%, and solid printing (solid printing, non-printing portions) and the photoreceptor were visually observed to confirm the presence or absence of filming. As shown in FIG. 3, when toner adhered to the photoreceptor, it was evaluated as x.
When filming occurs, image defects occur, the smoothness of the surface of the photoreceptor is impaired, and the quality becomes unstable over time.
(3) Toner leakage:
8,000 sheets of A4 paper were printed in the longitudinal direction at a coverage rate of 5%, and the presence or absence of toner leakage between the developing roller and the doctor blade was checked.
(4) Retention rate:
The tape was peeled off in a solid black (100% print density) printed area, and the image density was calculated from the ratio of the image densities before and after the tape was peeled off. That is, if the image density before tape peeling is ID (before) and the image density after tape peeling is ID (after), the fixing rate can be calculated by the following formula.
Fixing rate (%)=(ID (after)/ID (before))×100
Here, the tape peeling operation means that an adhesive tape (manufactured by Sumitomo 3M, trade name: Scotch Mending Tape 810-3-18) is attached to the measurement part of the test paper, pressed with a constant pressure to adhere, and then It is a series of operations to peel off the adhesive tape in the direction along the paper at a constant speed. Further, the image density was measured using a spectrophotometer (NF333 manufactured by Nippon Denshoku Co., Ltd.).

(5) Offset In an environment of temperature 20 to 25° C. and humidity 50 to 60%, it was visually confirmed whether there was dirt on the cycle of the fixing roller with a specific fixing pattern every 1,000 sheets of continuous printing.
(6) Fog density (carrier contamination)
In this evaluation, printing failure (image staining) was used as a criterion. The non-printed portion of the printed matter was measured with a spectrophotometer NF333 manufactured by Nippon Denshoku Co., Ltd. Taking 0.7 as a reference value for the fog value, it was confirmed visually that the non-image area was dirty when the value exceeded 0.7.
(7) Charge Amount In the case of one-component development, the charge amount on the developing roller was measured with an internal capacitor after the toner was sucked by a suction-type charge amount measuring device manufactured by Trek.
In the case of two-component development, an appropriate amount of the toner carrier mixture (hereinafter referred to as developer) on the magnet roller was sampled, the toner was attracted from the 635 mesh, and the charge amount was measured.
(8) Toner Concentration The developer on the magnet roller of two-component development was collected after printing, the toner was sucked from the 635 mesh, and the toner concentration was calculated from the remaining carrier amount.
(9) Image Density/Image Uniformity A magnetic one-component development printer is used to print solid black (print density: 100%), and the reflection density D of the printed area is measured using a spectral color difference meter (Nippon Denshoku NF333). image density.
Further, the printed black solid image was visually observed, and uniformity was evaluated as "x" when blurring occurred, and uniformity was evaluated as "good" when there was no blurring.

・Evaluation of single-component developing toner (non-magnetic) The spherical toners obtained in Examples 1 to 5 and Comparative Examples 1 to 4 were applied to a printer employing a single-component developing system at a line speed of 30 sheets/minute. was filled and the quality of the printed image was evaluated.
Table 3 shows the evaluation results.

Evaluation of Two-Component Developing Toner (Non-Magnetic) The pulverized toners obtained in Examples 6 to 8 and Comparative Example 5 were put into a two-component developing machine and printed. In the trickle development method, a developer was prepared by mixing 100 parts by weight of toner and 10 to 20 parts by weight of ferrite carrier with a DR mixer (200 rpm×10 minutes).

Then, a two-component development printer with a line speed of 35 sheets/minute was charged with the two-component toner prepared above, and the quality of the printed image was evaluated. For the evaluation, a 5% printing rate was used on A4 paper, and continuous printing was performed until fog due to carrier contamination occurred (approximately 10,000 sheets), and the following items were confirmed. The toner density was the value on the magnet roller when fogging occurred.
The evaluation results are shown below.

Evaluation of magnetic toner (single-component development) A printer with a magnetic single-component development system at a line speed of 38 sheets/min was filled with the magnetic toner obtained in Example 9 and Comparative Example 6, and the quality of printed images was evaluated. . Table 6 shows the evaluation results.

In Examples 1 to 3, good results were obtained in all of blade fusion, filming, toner leakage, fixation rate and offset, and excellent image quality was obtained.
When a hydrocarbon wax is used in a one-component developing system, filming may occur (Example 5). was gotten. That is, in the case of a simple hydrocarbon wax, since there is no reaction point (acid value: 0), it is possible that filming was affected. Therefore, when the acid value of the wax is more than 0 mgKOH/g, the image can be improved, and it is more preferably 0.05 mgKOH/g or more.

In Example 4, filming and toner leakage were evaluated as ◯, but blade fusion was Δ and offset was ×. and the offset was ◯.
In Comparative Example 5, there was carrier contamination and the toner concentration on the magnet roller was high. On the other hand, with the toners of Examples 6 to 8, the increase in toner concentration on the magnet roller was suppressed, and carrier contamination did not occur.
In Examples 6 to 8, it was confirmed that the addition of dimethylpolysiloxane as an internal additive did not affect the offset.

In Example 9, the image density was higher and the image uniformity was better than in Comparative Example 6 in which no dimethylpolysiloxane was added.
It is believed that the toners of Examples were prevented from exhibiting insufficient fluidity due to excess wax, fading due to poor charging, and non-uniformity, because exudation of wax was suppressed. Therefore, even when a large amount of wax is added to improve low-temperature fixability, a toner with high image quality can be obtained.

As described above, in the toners of Examples, the particle size hardly changed even when heated, and coalescence of the toner powder was preferably prevented. In both the spherical toner used in the one-component development system and the pulverized toner used in the two-component development system, it was possible to preferably prevent poor printing due to exudation of the wax.
Further, by using the toner of the present invention, high anti-offset property is obtained even in the case of low-temperature fixing, and filming on the photoreceptor, generation of carrier contamination, etc. can be favorably suppressed.
Further, by using the toner of the present invention, it was possible to preferably prevent blade fusion, photoreceptor filming, etc., without depending on the physical properties of the wax. In particular, not only the pulverized toner, but also the spherical toner subjected to the heat treatment process was able to preferably prevent poor printing due to exudation of the wax.

Furthermore, as a toner for printers and the like adopting one-component development and two-component development systems, 1 to 13 parts by weight of wax and 0.5 to 13 parts by weight of dimethylpolysiloxane are added to 100 parts by weight of binder resin. By kneading in a range of less than parts by weight, it was possible to preferably prevent printing defects due to exudation of the wax, and to preferably improve fixability even in low-temperature fixing.

Although one preferred embodiment of the invention is described above, the invention is not so limited. It is understood that various other embodiments can be made without departing from the spirit and scope of the invention. Furthermore, in this embodiment, the actions and effects of the configuration of the present invention are described, but these actions and effects are examples and do not limit the present invention.

Claims (9)

A toner for electrostatic charge image development containing a binder resin, a colorant, wax, and dimethylpolysiloxane as an internal additive. 2. The method according to claim 1, wherein the wax is contained in an amount of 1 part by weight or more and 13 parts by weight or less and the dimethylpolysiloxane is contained in an amount of 0.5 parts by weight or more and less than 5 parts by weight with respect to 100 parts by weight of the binder resin. Toner for electrostatic charge image development. 3. The toner for electrostatic charge image development according to claim 1, wherein the dimethylpolysiloxane is contained in an amount of 0.1 parts by weight or more and 1.0 parts by weight or less with respect to 1 part by weight of the wax. 4. The electrostatic image developing toner according to claim 1, further comprising at least one selected from the group consisting of amorphous silica and titanium oxide as an external additive. The toner for electrostatic image development according to any one of claims 1 to 4, wherein the wax is at least one selected from the group consisting of an ester wax and a Fischer-Tropsch wax. 6. The electrostatic image of claim 1, wherein the wax has a melting point of 65° C. or higher and 95° C. or lower, and an acid value of the wax of 0.1 mgKOH/g or higher and 25 mgKOH/g or lower. developer toner. 7. The toner for electrostatic charge image development according to claim 1, wherein the binder resin is a polyester resin. a kneading step of kneading a binder resin, a coloring agent, a charge control agent, a wax, and a dimethylpolysiloxane to obtain a kneaded product;
a pulverizing step of pulverizing the kneaded material to obtain a mother toner having an average particle size of 5 μm or more and 10 μm or less;
a pretreatment step of adding amorphous silica or titanium oxide to the mother toner;
a heat treatment step of heat-treating the mother toner;
A method for producing a toner for developing an electrostatic charge image comprising a kneading step of kneading a binder resin, a coloring agent, a wax, and a dimethylpolysiloxane to obtain a kneaded product;
a pulverizing step of pulverizing the kneaded material to obtain a mother toner having an average particle size of 5 μm or more and 10 μm or less;
an external addition step of adding amorphous silica and titanium oxide as external additives to the obtained heat-treated mother toner;
A method for producing a toner for electrostatic charge image development, comprising a carrier mixing step of mixing magnetic powder with the toner obtained in the external addition step.

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